I don't want any subdomains in my email addresses. What I did was erase my my hostname (www) from my domain then hit save thinking that would give me the email domain names I wanted. Then I added a cname record for (www) to redirect (www) to example.com.

I haven't had a chance to see if it fixed my email problem but it did break my website. I don't have www.example.com any more. I have tried changing things back the way they were but it does nothing.